The present invention relates to a shift control device for a vehicle for changing a shift range of the vehicle.
A so-called electric shifter device, in which a position of an operational member which corresponds to a shift lever is detected electrically for shifting, is known as a shift control device for a vehicle. This electric shifter device has been widely used in electric vehicles or hybrid vehicles which do not have a mechanical transmission. However, the electric shifter device which does not require a mechanical connection between the operational member and the transmission is superior in design flexibility, so that there is a tendency that vehicles provided with the mechanical transmission, such as conventional vehicles which install an engine (internal combustion engine) only as a power source, use the electric shifter device.
In the electric shifter device having less limitation in the operational amount and the operational direction of the operational member, a dial type of operational member in which a traveling range is changed according to rotation and the like of the operational member has been considered from viewpoints of the compactness and the operability. That is, the dial type of operational member can shorten its operational stroke and make its size compact properly, and also since it may be unnecessary for a driver to move a wrist greatly when operating the operational member and the driver may operate the operational member without seeing, the superior operability can be provided. A device disclosed in Japanese Patent Laid-Open Publication No. 2010-105621 is known as an example of the above-described electric shifter device.
In the device of this patent document, a rotatable operational knob is provided, and the shift range is changed to a neutral range when this operational knob is slid along a specified axial line, and also the shift range is changed to a drive range or a reverse range when the operational knob is rotated further from its slid position after the operational knob is slid.
Further, in the electric shifter device, a so-called momentary type of mechanism, that is—a mechanism to return the operational member toward a specified home position automatically as soon as holding of the operational member by a driver's hand is released, has been widely used in order to improve the compactness or the operability. A device disclosed in Japanese Patent Laid-Open Publication No. 2010-105623 is known as an example of this momentary type of electric shifter device.
Specifically, in the device of this patent document, the operational member which can be slid and rotated is provided, and the shift range is changed to the neutral range when the operational member is slid from the home position. When holding of the operational member by a driver's hand is released in this state, the operational member is returned to the home position, keeping the neutral range. Further, when the operational member is further rotated after it is slid from the home position, the shift range is changed to a traveling range (the drive range or the reverse range). When the holding of the operational member by the driver's hand is released in this state, the operational member is returned to the home position, keeping the changed shift range.
There recently exit vehicles in which a shift mode is changeable through a driver's operation of a specified operational member according to driving conditions or driver's requests. For example, some vehicle provided with an engine is configured to have a mode having a relatively small gear ratio to provide a better fuel economy or a mode having a relatively large gear ratio to provide a higher traveling responsiveness, in addition to a normal mode.
Herein, the device of the above-described second patent document is configured to change the shift range (to the neutral/drive/reverse rages) only by operating the operational member. Therefore, there is a problem in that in a case in which the device of the second patent document is applied to the vehicle configured as described above, it may be required to provide another operational member for changing the shift mode, additionally to the operational member for changing the shift range, so that this device may be improperly complex and also the operability of these plural operational members operated by the driver may improperly deteriorate.